Looks very nice
Some screenshots...
Red: Add a clip brush somewhere here.
Red: Add two more clip brushes here.
Red: I'd prefer a wall like this to avoid the height change in the corner that doesn't look nice.
Red: All barrels are way too fat. That doesn't look realistic and the top textures are misaligned because of the wrong texture size.
Red: Add one more clip brush below the ladder that people can't jump under it.
Red: The right side (and left down) looks very strange, because the rest of the maps is mapped like the green area.
Red: Move this wood texture a little bit that the dark line of the plank disappears.
Green: This box is misaligned.
Red: Maybe rotating this face like you did on the left side would look more clean, because it's the same structure with a different texture alignment at the moment.
Red: This face is misaligned at the red base.
Red: This faces on the red side of the map are slightly misaligned, too.
Red: The lighting looks very strange here. It would be cool if you can fix the lighting here a little bit to avoid this broken shadows.
Great job so far
Map is online @ [OTB] Beta!